The fees for taking the CAPM exam are $300 if you're not a PMI member, and $225 if you are PMI member. PMI membership costs $129, so you will pay $354 if you become a PMI member and then take the CAPM exam, which is more than you would have paid if you're not a member. Unlike the PMP exam, there is no saving if you do this. The fees are the same for paper based tests (PBT) and computer based tests (CBT).
The fees are the same across the world and they are set by PMI (and not by Prometric).